If it says "command not found" or similar try this: Add the bin\ directory (e.g. C:\Program Files\Java\jdk1.7.x_xx\bin) of the installed JDK to the PATH environment variable, as described here: http://www.java.com/en/download/help/path.xml

Download Eclipse IDE (same bit version as for the JRE, i.e. 32 or 64 bit) and unzip